JP3314244B2 - Optical card - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an optical card capable of optically recording information.

[0002]

2. Description of the Related Art Hitherto, a so-called optical card has been known as an optical memory card in which an information recording section is built in a plastic card. Among them, the manufacturing process is simple,
The raw material is not limited to a specific optical recording material, and as an optical card using an optical recording medium with a low manufacturing cost suitable for mass-scale duplication on an industrial scale, the low-reflectance portion has light scattering properties. There has been proposed an optical card composed of a roughened portion having the following (see, for example, Japanese Patent Application Laid-Open No. 1-1055791).

[0003] The WORM (Write O)
FIG. 4 shows an example of the “nice read many” type. The optical card shown in FIG. 4 includes a roughened low-reflectance portion 42 of a light-transmitting substrate 40, an optical recordable portion 41 having a high reflectivity, and an optical recordable portion 4.
An optical recording material layer 43 is formed on the surface of the base material 40 so as to cover the low reflectance portion 42 with the optical recording material layer 1, and an adhesive layer 44 and a card base material 45 are further formed on this surface.
On the other hand, on the opposite side, a transparent base material layer (protective layer) 46 and a surface hardened layer 47 are formed by lamination. Since the optical recording material layer 43 is not exposed at the end of the card and has no voids as a whole, it is particularly excellent in stability over time.

[0004] Recording on the optical card is performed by making a hole 48a on the optical recording material layer 41 using a laser beam. The recorded information is read by an optical record reading device.

[0005]

Although the optical card and the optical recording and reading apparatus are becoming popular, there is a problem that the optical card may be forged or imitated.

SUMMARY OF THE INVENTION It is an object of the present invention to solve the above-mentioned problems and to provide an optical card which has been subjected to forgery prevention processing and can be distinguished from a counterfeit product.

[0007]

In order to achieve the above-mentioned object, the present invention provides a light-transmitting substrate formed on one side of a light-transmitting substrate.
A card substrate is laminated via an adhesive layer on the surface of an optical recording material layer for performing optical recording, and a transparent protective layer and a surface opposite to the surface on which the optical recording material layer of the substrate is provided. In an optical card having a surface hardened layer laminated thereon, a portion corresponding to the optical recording material layer on the card base material is indistinguishable visually under normal light, and is irradiated with a light of a specific wavelength. And a printing layer having information that can be identified by the printing layer. Further, the present invention is characterized in that the printing layer is formed of a fluorescent ink. Further, the present invention is characterized in that the printing layer is formed of an ink that absorbs or reflects a special wavelength.

[0008]

The optical card having the above-mentioned structure is obtained by irradiating a portion corresponding to the optical recording material layer on the card base material with a light beam having a specific wavelength, which cannot be visually distinguished under a normal light beam. The provision of the printed layer having identifiable information makes it difficult to forge the card. Even if a counterfeit product is manufactured, it will not be mistaken for a counterfeit product by the information in the printed layer.

[0009]

FIG. 1 is a sectional view of a WORM type optical card according to an embodiment of the present invention, which corresponds to the xy sectional view of an optical card C shown in FIG. An optical card C shown in FIG. 1 has a card base 4 laminated on an optical recording material layer 2 formed on one surface of a light-transmitting base 1 via an adhesive layer 3. A transparent protective layer 5 and a hardened surface layer 6 are laminated on the surface opposite to the side on which the optical recording material layer 2 is provided. The card base material 4 includes an oversheet 4a, a core sheet 4b, and an oversheet 4.
c having a three-layer structure, wherein printed layers 7a and 7b are provided between the oversheet 4a and the core sheet 4b on the optical recording material layer 3 side, and between the oversheet 4c and the core sheet 4b. Is provided with a printing layer 7c.

In the present application, the printed layer 7b having information which is indistinguishable visually under a normal light beam and has information which can be identified by irradiating a light beam of a specific wavelength on the core sheet corresponding to the optical recording portion. Is provided. Specifically, the printing layer 7b is provided with an ink that is visually indistinguishable under normal light rays and that can be identified by irradiating light rays of a specific wavelength. Alternatively, by forming the printing layer 7b with two or more kinds of inks having different properties, the appearance is a solid printing layer, but information such as characters or patterns is read by a reading method according to each property. To form a printed layer.

An example of the ink used here and the method of using it will be given. First, UVS CAR MC colorless fluorescent ink and SSPC colorless fluorescent GOF-A (manufactured by The Inteck Co., Ltd.) are examples of inks that cannot be visually discriminated in appearance. Using these inks, printing on the card is formed by offset or silk printing. If the solid sheet is printed with offset ink, the oversheet 4a will not be joined to the core sheet 4b during hot pressing, but if silkscreen ink is used, the oversheet 4a will be joined. Printed designs and characters are under normal light,
It cannot be identified. When reading the print, the print can be read like normal print by irradiating light of a wavelength at which the ink develops color.

Next, as an example of using two or more kinds of inks having different properties, there is an ink which absorbs or reflects a special wavelength and has the same color in appearance. The patterns and the like printed with these inks cannot be identified because they are the same color in appearance, but can be identified by irradiating a light beam having a special wavelength. For example, a barcode is printed using ink that absorbs a special wavelength, and a negative barcode pattern is printed using ink that reflects the same wavelength.
Then, the bar code pattern can be read by irradiating light of a special wavelength, although it looks like only solid printing of one color.

[0013] Inks absorbing special wavelengths include UV.
SCARM black PW, and ink that reflects a special wavelength include UVS CAR Security Black Conc (manufactured by The Inktech Co., Ltd.). Both of these inks have a black color.

The optical card C shown in FIG. 1 is created by the process shown in FIG. Hereinafter, this step will be described in order.

First, a roughened master having a low-reflectance portion roughened according to the information recording pattern is prepared.

As a first step, a transparent substrate (400 μm thick)
m acrylic plate) is uniformly coated with a photoresist to a thickness of 5000 ° by a rotary photoresist coating machine to form a photoresist layer. As the photoresist, "Microposit 1400 manufactured by Shipley Co., Ltd." which is a positive resist (quinonediazide system) was used. Next, as a second stage, after a photomask formed according to the information recording pattern is superimposed on the photoresist layer using a mask alignment device, the first exposure (patterning exposure) with ultraviolet light is performed.

Subsequently, as a third step, a glass plate having one surface roughened into fine irregularities (average roughness 0.3 μm, #
Exposure again using 3000 polished glass (roughening exposure)
I do. After exposure, as a fourth step, when the photoresist layer is developed, the photoresist exposed to the ultraviolet rays flows away, the photoresist not exposed remains, and the pattern of the photomask is transferred onto the transparent substrate. . As a result, a photoresist layer having a roughened surface is formed as a guide track having a width of about 2.5 μm and a pitch of about 14.5 μm, for example.

Next, an optical recording medium on which an information recording pattern composed of a low-reflectance portion having a roughened surface is formed is used as a roughened original, and a mother mask is formed from the roughened original by a molding press. Duplicate.

Specifically, the above-mentioned resin was prepared on a transparent substrate (acrylic plate having a thickness of 1.2 mm) via a molding agent made of a molding resin of an ionizing radiation-curable resin or a thermosetting resin. After irradiating the UV light with the roughened original plate laminated and pressed by a press machine, release the roughened original plate and the transparent base material, duplicate the pattern on the transparent base material side, and apply a mother mask. Form. In this embodiment, as a molding resin, a UV curable resin (manufactured by The Inktec, SEL-XA (mainly composed of a polyester acrylate oligomer and neopentyl glycol diacrylate monomer, Irgacure 18) is used.
4 (to which a photopolymerization initiator) was added)).

On the other hand, a hardened surface layer 6 is formed on a transparent base material to be the transparent protective layer 5 of the optical card C.

Here, as a substrate to be the transparent protective layer 5,
Polycarbonate (PC) having a thickness of 400 μm was used. In addition, polymethyl methacrylate (PMMA), acrylonitrile-styrene copolymer (AS resin), cellulose propionate (CP), cellulose acetate butyrate (CAB), polyvinyl chloride (PVC), polyester, and the like can be used. However, in this embodiment, a PC having a small birefringence is used. As the surface hardened layer 6, an acrylic UV curable hard coat agent (UH-00, manufactured by Toray)
1) was used. In addition, UV curable resin (oligomer,
Monomer initiator), and a thermosetting resin such as a melamine resin. Then, the above hard coating agent was applied on a PC substrate by spinner coating, and was cured by irradiating ultraviolet rays. In a normal case, it is necessary to apply a primer coat on the surface opposite to the surface hardened layer 6 in order to impart adhesiveness to a duplication resin described later. Has no primer coat because of its good adhesion to the replication resin.

Next, using the mother mask as a replication master for mass replication, the optical recording medium is replicated on the back side of the base material to be the transparent protective layer 5 by molding.

Specifically, after duplicating resin is sandwiched between the back side surface of the base member 5 and the pattern surface of the mother mask, the substrate is pressed with a pressing machine and irradiated with ultraviolet rays. The mold is released and the pattern is duplicated on the substrate 5 side. Thus, a low-reflectance portion is formed on the surface of the duplication resin, and this duplication resin becomes the light-transmitting base material 1 of the optical card C. In this example, an ultraviolet-curing resin (manufactured by ThreeBond, SS-120, urethane acrylate) was used as the replication resin.

Subsequently, an optical recording material layer 2 is laminated on a part of the light transmissive substrate 1 made of a duplication resin so as to cover a low reflectance portion of the substrate.

Specifically, a laminated film of a TeOx film and a TeOy film (x = 0.5, y = 1.8) is formed to a thickness of 500 ° by using a reactive sputtering apparatus. Was formed.

Aside from the above series of steps, a card base material 4 is prepared. In the card base material in the present embodiment, printed layers 7a and 7b are provided on the optical recording material layer 3 side of the core sheet 4b, and a printed layer 7c is provided on the opposite side. The oversheet layer 4a is formed on the print layers 7a and 7b by bonding the oversheet layer 4b on the print layer 7c.

As the core sheet, milk white vinyl chloride, polycarbonate, cellulose acetate butyrate (C
AB), cellulose acetate propionate (CA
P) and the like, and the thickness is 180-220 μm.
m.

According to the present invention, the printed layer 7 on the core sheet has information which cannot be visually discriminated under normal light, and has information which can be identified by irradiating a light of a specific wavelength.
b is provided. As the ink to be used, the above-described ink can be used as appropriate according to the intended use, but here, as the ink which is visually indistinguishable in appearance, S
SPC colorless fluorescent GOF-A (The Inktec Co., Ltd.)
) Is used to form the print layer 7b by offset printing.

On the optical recording material layer side on the core sheet,
The printing layer 7a provided in a portion other than the printing layer 7b and the printing layer 7c on the opposite side of the core sheet can be printed with characters and patterns as in the related art. Also in this case, when the solid is printed with the offset ink, the oversheet 4a does not join with the core sheet 4b at the time of hot pressing.
It is preferable that a and 7c are also formed by silk screen printing.

For the purpose of protecting the printed layers 7a, 7b and 7c, oversheet layers 4a and 4c can be further provided on the printed layers. This oversheet layer is made of a material such as transparent vinyl chloride, transparent CAB, and transparent CAP. By providing oversheet layers on both sides of the core sheet,
Since the card base 4 has a three-layer structure, no warpage occurs during hot pressing.

Then, the card substrate 4 is bonded and laminated to the substrate 1 provided with the optical recording material layer 2 via the adhesive layer 3. Specifically, “Toray UH-1260C” (two-component curing type) was used and bonded at a normal temperature to a thickness of 60 μm. In this case, since the adhesive layer 3 is in direct contact with the oversheet 4a (transparent polyvinyl chloride) of the card base material 4 over the entire surface, the adhesive layer 3 is firmly adhered. The blank produced as described above is stamped on a card base material to produce an optical card C shown in FIG.

Printed patterns and characters cannot be identified under normal light, but when reading a print, irradiate with light having a wavelength at which the used ink develops color.
The print could be read like a normal print.

[0033]

As described above, according to the present invention,
On a portion corresponding to the optical recording material layer on the card substrate,
The printed layer, which cannot be visually identified under normal light and has information that can be identified by irradiating a light of a specific wavelength, is provided, thereby preventing forgery of the optical card. Also, by putting specific information in the print layer,
The printed layer can also be used for product management.

[Brief description of the drawings]

FIG. 1 is a sectional view of an optical card according to an embodiment of the present invention.

FIG. 2 is a plan view of an optical card according to an embodiment of the present invention.

FIG. 3 is a process chart for manufacturing the optical card C shown in FIG.

FIG. 4 is a sectional view showing a conventional optical card.

FIG. 5 is an enlarged view of an optical recording unit.

[Explanation of symbols]

C Optical card 1 Optically transparent substrate 2 Optical recording material layer 3 Adhesive layer 4 Card substrate 4a, 4c Oversheet 4b Core sheet 5 Transparent protective layer 6 Surface hardened layer 7a, 7c Printing layer 7b Under normal light A printed layer that is indistinguishable visually and has information that can be identified by irradiating a light beam of a specific wavelength

Claims (3)

(57) [Claims] 1. A card substrate is laminated via an adhesive layer on a surface of an optical recording material layer for optical recording formed on one surface of a light-transmitting substrate, and the optical recording of the substrate is performed. In an optical card in which a transparent protective layer and a surface hardened layer are laminated on the surface on the side opposite to the side on which the material layer is provided, a portion corresponding to the optical recording material layer on the card base material, An optical card comprising a printed layer provided with information that cannot be visually identified under a light beam and has information that can be identified by irradiating a light beam of a specific wavelength. 2. An optical card according to claim 1, wherein said printing layer is formed of a fluorescent ink. 3. The optical card according to claim 1, wherein said printing layer is formed of ink absorbing or reflecting a special wavelength.